```Question 406758
1)What probability value would be needed to complete the following probability distribution?x -2 -1 0 1 2
P(x) 0.14 0.14 0.12 0.30
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The P(x) listed add up to 0.7; you need 0.3 to complete the distribution.
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2)Find the mean of the distribution shown.x -3 -2 -1 0
P(x) 0.20 0.24 0.48 0.08

Multiply each x value by its probability.
Add up the four products to get:
x-bar = -1.5
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3) A university has 10,000 students of which 8000 are male and 2000 are female. If a class of 30 students is chosen at random from the university population, find the mean and variance of the number of male students
male mean = np = 30*0.8 = 24
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4)Find the mean of the distribution shown.
x 1 2
P(x) 0.25 0.75
Same procedure as #2
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5)Find the mean of the distribution shown.
x 4 6
P(x) 0.32 0.68
Same procedure as #2
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6)A computer store has 50 printers of which 30 are laser printers and 20 are ink jet printers. If a group of 10 printers is chosen at random from the store, find the mean and variance of the number of ink jet printers.
mean = np = 10*20/50 = 4
variance = npq = 4*30/50 = 12/5 = 2.4
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7)Find the mean of the distribution shown.
x 0 3 5
P(x) 0.30 0.24 0.46
Same as #2
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8)What value would be needed to complete the following probability distribution?

0 1/3 = 8/24
1 1/8 = 3/24
2 1/8 = 3/24
3
4 1/6 = 4/24
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Missing 6/24 = 1/4
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cheers,
Stan H.
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```